Based on the observation of collective actions of the families losing the only child and the government's responds in recent years,this article uses the Davies J-curve theory model and comes up to the conclusion.That is,the families losing the only child have a rising value expectations to the government,while the corresponding level of the government's value ability remains at a rather low level and increases slowly with time.As a result,the gap between the value expectations and the value ability is widening.All of these may result in the f...